Hello, welcome to the website. My name isXXXXX can assist you with this.
Somebody will still own the land so it's not as easy as just deciding to take ownership of it.
If you try to adversely possess it then you would need to take control of it and exclude anybody else.
You would need to do this for 12 years. For a road, that might prove difficult, at least without alterting the true owner.
if all the residents of the street decide to make the surface to a good and safe state could we be liable
Yes, you could be, as you would be trepassing on somebody elses property.
The true owner might be rather grateful you've maintained it, but you just don't know for sure.